Welders' masks or helmets are known in the prior art and have been used for years to protect the face and head of a welder as he welds. One such example of a welder's mask is found in U.S. Pat. No. 1,601,830 issued Oct. 5, 1926, the disclosure of which is incorporated herein by reference. Generally, welders' helmets include a lens area through which the welder views his work as he welds. There have been many developments with respect to these lens packs including auto darkening lenses, special filter lenses, and other various lens systems for special purpose welding and the like. Traditionally, these lens packs include an outer protective cover lens, a middle light filtering lens for protecting the welder's eyes from the intense light generated during welding, and a rear cover lens. With the new auto darkening electronic lens packages, a protective outer or cover lens is provided and the electronic lens package is generally held in place with some type of spring loaded structure or otherwise to accommodate its being removed. However, it is not believed that any prior art welder's helmet provides for the ready removal and replacement of all of the lenses contained within a traditional lens pack, an electronic auto darkening lens package including cover lens, or the like, or that the techniques and structure used for holding these lens packs are particularly adapted to their ready changeout as might be desired when a welder moves from one type of welding to another.
In order to solve these and other problems found in the prior art, and as an advancement in the art of welders' helmets, the inventor has succeeded in designing and developing a welding helmet having a removable face plate assembly, the face plate assembly comprising a cartridge for sliding insertion into a slot in the helmet with an interlocking mechanical latch mechanism for securing the cartridge in place. The cartridge itself has a picture frame slot accessible from the side of the cartridge into which a protective cover lens may be slidingly inserted for protecting the other lenses contained within the cartridge. The cartridge also includes a removable frame which has a plurality of retention clips which are integrally formed with the frame but resilient so as to provide a spring pressure against additional lenses which the frame holds in place immediately behind the face lens. The frame itself is held in place by a plurality of tabs and slots in the sides of the cartridge and frame so that the frame may be mechanically positively secured within the cartridge and avoid its inadvertent release therefrom which might otherwise discharge the lenses from the cartridge and cause their damage. This is undesirable both to avoid the expense of damage to what may be very expensive lenses as well as a safety hazard which might be encountered should the welder be welding and the protective lenses inadvertently fall out of their desired shielding orientation within the cartridge in front of the welder's face and eyes. Additionally, the receiving slot in the face of the welder's mask provides for the cartridge to be inserted at the top of the slot with the bottom of the slot providing a mechanical step for the cartridge to prevent its falling down and out of the welder's helmet. Furthermore, an extended lip surrounds the periphery of the slot opening which matches and lines up with the frame so that the frame is mechanically captured within the cartridge when the cartridge is inserted and locked in place within the welder's helmet.
Thus, the present invention allows for a welder to readily remove the lens cartridge by merely separating a nib and hole which releases the cartridge for being lifted out of its slot. Once removed, a second cartridge may already be prepared with different lenses to accommodate the welder's desire to change to different lenses, or some other application merely by slipping the second cartridge into the slot and securing it with the nib and hole. Furthermore, should the protective face lens be damaged by flying debris, it may be readily replaced by removing the cartridge and removing the face lens by sliding it sideways out of its receiving slot with a replacement face lens being inserted by reversing the process. Should the welder desire merely to maintain his same cartridge and yet remove and replace lenses, this is readily achieved by removing the frame from the cartridge by disengaging the tabs and slots in the sides of the cartridge and frame which permits access directly to the lenses for their removal and replacement.
The present invention provides ready access, removability, and replacement capabilities for the face lens and other protective lenses commonly found in a welding helmet without the use of tools, in a quick and easy fashion, without hampering or compromising the desired safety and reliability of the welding helmet itself.
While the principal advantages and features of the present invention have been briefly explained, a fuller understanding of the invention may be gained by referring to the drawings and Description of the Preferred Embodiment which follow.